Approach:
This project incorporates components of two former research projects on management of livestock stress and genetic factors related to disease susceptibility. Stress response evaluation utilizes physiological (respiration rate, health status, etc.), physical (body temperature, coat color, etc.), and behavioral (temperament, eating, etc.) measurements to characterize the impact of stress (particularly environmental) on feedlot cattle. These measurements will be refined to provide dynamic response evaluations in a feedlot setting, both for data collection and as potential management tools. The results will provide risk assessment models to assist producers in identification of animals that would most benefit from changes in management (shade, sprinklers, etc.). In addition, weather data will be utilized to provide advanced warnings to producers of impending environmentally stressful conditions to cattle. Genetic diversity for stress traits among several breeds will be characterized to identify breed differences and suggest management alternatives based on genotype. Also, criteria of ventilation requirements for swine production will be updated for modern lean high growth rate animals and ration formulations. Livestock will be observed in production feedlot settings or in controlled environment chambers to provide suitable environmental and management control. The feedlot includes modern animal handling facilities to individually manage cattle or provide group penning of cattle with or without shade. Environmental chambers provide precision control of environmental factors (temperature, humidity, and light) in close proximity of calorimeter equipment to measure energy expenditure of livestock. The availability of a wide range of cattle breeds, extensive animal handling and technical expertise, and animal health practitioners provides the necessary resources for conducting basic and applied research.